【作者】 刘静；

【导师】 丁为民；

【作者基本信息】 南京农业大学 ， 农业生物环境与能源工程， 2009， 硕士

【摘要】 本文针对养猪废水中有机污染物和氨氮(NH3-N)浓度高、悬浮物含量高的特点,采用循环流人工湿地(circle-flow constructed wetland, CFCW)工艺对养猪废水进行处理,研究CFCW处理养猪废水的效能,并针对人工湿地天然钙型沸石吸附NH3-N饱和的现象进行了再生研究。主要结果如下：1、以天然钙型沸石为研究对象,利用序批式试验探讨了天然钙型沸石对NH3-N的吸附性能,天然钙型沸石对NH3-N的吸附等温线符合Freundlich方程,饱和吸附容量能达到38.18mg/g。2、研究填料天然钙型沸石对吸附NH3-N饱和的天然钙型沸石(简称铵沸石)的曝气再生及化学再生进行了初步研究。曝气再生试验研究了曝气强度对铵沸石再生的影响,在设定的四种曝气强度下,与自然再生进行对比得知,铵沸石在曝气量20ml/min条件下再生效果最好,曝气再生41 d后,NH3-N、MO3--N(硝态氮)均有显著上升,NH3-N浓度达到43 mg/L,NO3--N浓度达到68 mg/L。3、通过筛选并优化化学再生剂使用条件的试验结果表明：综合对比分析6种常用化学再生剂,NaCl+CaCl2组合再生剂是铵沸石的最佳再生剂；在30℃-55℃温度范围内,温度越高,沸石再生效果越好,且再生4h后NH3-N解析量上升显著；pH值在3-11变化时,铵沸石的再生效果受pH值影响较小；综合考虑再生效率及成本,当组合再生剂用量为0.64 mol/L,或NaCl:CaCl2=7:3时沸石再生效果最佳。4、以养猪模拟废水为处理对象,考察了CFCW的去运行情况。在湿地系统运行阶段,进水NH3-N浓度在600-800 mg/L的高浓度,出水NH3-N在150-260 mg/L,系统对NH3-N的去除率为61%-76%,而在一年多前的湿地系统启动阶段,进水NH3-N浓度为558-883 mg/L,而系统出水浓度却小于0.1 mg/L, NH3-N去除率高达99.9%以上；湿地系统对NH3-N去除不但有明显的下降,而且系统出水远高于养猪废水NH3-N最大排放标准为80mg/L的要求,历时一年多高NH3-N负荷的运行已经使人工湿地中的钙型沸石对NH3-N的吸附达到饱和。湿地运行阶段进水CODcr浓度为250-500 mg/L,系统出水CODcr浓度在30～80 mg/L,系统对CODCr的去除率为78%～92%,与人工湿地初期阶段CODCr处理效果相比,系统对CODCr的去除效果较好,CODCr去除率仅仅下降了8%。CFCW曝气再生试验表明：曝气后人工湿地系统中出水NH3-N浓度总体趋势增加,最高浓度可达400 mg/L,浓度增加150 mg/L多,沸石再生效果明显。对CFCW进行NaCl+CaCl2再生化学再生试验,出水NH3-N浓度由化学再生前的350 mg/L上升到533mg/L,浓度增加200 mg/L多。增加曝气和添加组合化学剂NaCl+CaCl2,均可实现铵沸石再生,且再生效果良好。更多还原

【Abstract】 Research on the efficiency of circle-flow constructed wetland (CFCW) process for swine wastewater treatment because of high concentrations of organic contamination, ammonia nitrogen (NH3-N), and suspended solids in swine water. Testing natural Ca-form zeolite’s regeneration process to resolve the problem that zeolite adsorbs NH3-N becoming saturation. Main results are as follows:1 Through a serious of sequence batch experiments, researching the NH3-N adsorption capacity of natural Ca-form zeolite, The results show that the adsorption isotherm of Ca-zeolite for NH3-N consistents with Freundlich equation, and the maximal adsorption capacity is as high as 38.18 mg/g.2 Researching on the efficiency of aeration regeneration and chemistry regeneration to NH4+-zeolite by seting 4 kinds of aeration intensities and studying the effect of aeration intensity on NH4+-zeolite regeneration, and comparing with natural regeneration, NH4+-zeolite aeration regenerate is best when aeration intensity is 20 ml/min. NH3-N and NO3--N have notable go up equally after 41 d, NH3-N reaches 43 mg/L, NO3--N reaches 68 mg/L.3 Comprehensively comparing the regeneration effects of select the best chemistry regeneration solvent from six different chemistry solvents, and optimize the working conditions of the best chemical solvent., the regenerate containing CaCl2 and NaCl have the optimal regeneration effect. With the temperature increasing, the regeneration effect of NH4+-zeolite is increased correspondingly, and the release rate of NH3-N increases significantly after 4 hour’s regeneration. With pH ranging from3.0 to 11.0, the regeneration effect of NH4+-zeolite is similar. Comprehensively considering the regeneration cost and the efficiency, when the useful content of regenerant is 0.64 mol/L, the ratio of NaCl to CaCl2 is 7 to 3, the natural Ca-form zeolite have optimal regeneration effect.4、Taking the simulated swine wastewater as the object to inspect the efficiency of CFCW for swine wastewater treatment. In CFCW operated stage, NH3-N high concentration entering constructed wetland system is between 600 and 800 mg/L, NH3-N concentration leak from constructed wetland system is 150-260mg/L, the elimination rate of system to treat NH3-N reachs 61% to 76%, but in the stage of CFCW start, the NH3-N concentration of entering constructed wetland system is 558～883 mg/L, but the NH3-N concentration leak from constructed wetland system is less than 0.1 mg/L, the elimination rate reaches as high as 99.9%. elimination rate of NH3-N in the CFCW does not drop, but also the NH3-N concentration leak from constructed wetland system higher than the requests that raises pigs the waste water NH3-N biggest emission standard is 80 mg/L. Natural Ca-form zeolite in CFCW has achieved saturated to the NH3-N adsorption after a year. Constructed wetland operation stage, the CODCr concentration entering constructed wetland system is 250～500 mg/L, leak from constructed wetland system is 30～80 mg/L, elimination rate of the constructed system for CODCr is about 78%～92%, but comparing with CFCW start stage, the removal effect of CODCr is good, its removal just drop about 8%Aeration regeneration experiments on CFCW indicate that NH3-N concentration in CFCW reach nearly 400 mg/L, NH3-N 150 mg/L, NH4+-zeolite regenerative effect is obvious. Chemistry regeneration on CFCW, the NH3-N concentration increase from 35 mg/L to 533 mg/L, rising more than 200 mg/L. Test results show that the increased aeration and add combinatorial chemistry NaCl+CaC2 regeneration, and NH4+-zeolite regenerative effect is better.更多还原